MyChem.info documentation¶
Introduction¶
MyChem.info provides simple-to-use REST web services to query/retrieve chemical and drug annotation data. It’s designed with an emphasis on simplicity and performance.
Quick start¶
MyChem.info provides two simple web services: one for querying chemical compound or drug objects and the other for chemical/drug annotation retrieval by common IDs (e.g. inchikey, chebiID, pubchem ID etc.). Both return results in JSON format.
Chemical/drug query service¶
URL¶
http://mychem.info/v1/query
Examples¶
http://mychem.info/v1/query?q=imatinib
http://mychem.info/v1/query?q=_exists_:chebi
http://mychem.info/v1/query?q=_exists_:drugcentral.bioactivity.uniprot.uniprot_id&fields=drugcentral.bioactivity.uniprot
Hint
View nicely formatted JSON result in your browser with this handy add-on: JSON formatter for Chrome or JSONView for Firefox.
To learn more¶
- You can read the full description of our query syntax here.
- Try it live on interactive API page.
- Batch queries? Yes, you can. do it with a POST request.
Chemical/drug annotation service¶
URL¶
http://mychem.info/v1/chem/<chem_id>
<chem_id> can be any one of the following common chemical/drug identifiers:
Examples¶
http://mychem.info/v1/chem/KTUFNOKKBVMGRW-UHFFFAOYSA-N
http://mychem.info/v1/chem/CHEBI:45783?fields=chebi
http://mychem.info/v1/chem/CHEMBL941?fields=chembl
http://mychem.info/v1/chem/BKJ8M8G5HI?fields=unii
To learn more¶
- You can read the full description of our query syntax here.
- Try it live on interactive API page.
- Yes, batch queries via POST request as well.
Documentation¶
Chemical annotation data¶
Data sources¶
We currently obtain chemical annotation data from several data resources and keep them up-to-date, so that you don’t have to do it:
* key name: this is the key for the specific annotation data in a chemical object.
The most updated information can be accessed here.
Note
Each data source may have its own usage restrictions. Please refer to the data source pages above for their specific restrictions.
Chemical object¶
Chemical annotation data are both stored and returned as a chemical object, which is essentially a collection of fields (attributes) and their values:
{
"_id": "KTUFNOKKBVMGRW-UHFFFAOYSA-N",
"unii": {
"_license": "http://bit.ly/2Pg8Oo9",
"inchikey": "KTUFNOKKBVMGRW-UHFFFAOYSA-N",
"ingredient_type": "INGREDIENT SUBSTANCE",
"inn_id": "8031",
"molecular_formula": "C29H31N7O",
"ncit": "C62035",
"preferred_term": "IMATINIB",
"pubchem": "5291",
"registry_number": "152459-95-5",
"rxcui": "282388",
"smiles": "CN1CCN(CC2=CC=C(C=C2)C(=O)NC3=CC(NC4=NC=CC(=N4)C5=CC=CN=C5)=C(C)C=C3)CC1",
"unii": "BKJ8M8G5HI"
}
}
The example above omits many of the available fields. For a full example, check out this example chemical, or try the interactive API page.
_id field¶
Each individual chemical object contains an “_id” field as the primary key. Where possible, MyChem.info chemical objects use InChIKey (a 27 character hash of the International Chemical Identifier) as their “_id”. If an InChIKey isn’t available, any one of the following datasource IDs may be used:
_score field¶
You will often see a “_score” field in the returned chemical object, which is the internal score representing how well the query matches the returned chemical object. It probably does not mean much in chemical annotation service when only one chemical object is returned. In chemical query service, by default, the returned chemical hits are sorted by the scores in descending order.
Available fields¶
The table below lists all of the possible fields that could be in a chemical object, as well as all of their parents (for nested fields). If the field is indexed, it may also be directly queried.
| Field | Indexed | Type | Notes |
|---|
Data release notes¶
This page contains metadata about each MyChem.info data release. Click a link to see more.
MyChem Releases¶
Loading release data . . .
Chemical query service¶
This page describes the reference for MyChem.info chemical query web service. It’s also recommended to try it live on our interactive API page.
Service endpoint¶
http://mychem.info/v1/query
GET request¶
Query parameters¶
fields¶
Optional, a comma-separated string to limit the fields returned from the matching chemical/drug hits. The supported field names can be found from any chemical object (e.g. here). Note that it supports dot notation, and wildcards as well, e.g., you can pass “chebi”, “chebi.name”, or “dbnsfp.products.*”. If “fields=all”, all available fields will be returned. Default: “all”.
size¶
Optional, the maximum number of matching chemical hits to return (with a cap of 1000 at the moment). Default: 10.
from¶
Optional, the number of matching chemical hits to skip, starting from 0. Default: 0
Hint
The combination of “size” and “from” parameters can be used to get paging for large query:
q=chebi.name:acid*&size=50 first 50 hits
q=chebi.name:acid*&size=50&from=50 the next 50 hits
fetch_all¶
Optional, a boolean, which when TRUE, allows fast retrieval of all unsorted query hits. The return object contains a _scroll_id field, which when passed as a parameter to the query endpoint, returns the next 1000 query results. Setting fetch_all = TRUE causes the results to be inherently unsorted, therefore the sort parameter is ignored. For more information see examples using fetch_all here. Default: FALSE.
scroll_id¶
Optional, a string containing the _scroll_id returned from a query request with fetch_all = TRUE. Supplying a valid scroll_id will return the next 1000 unordered results. If the next results are not obtained within 1 minute of the previous set of results, the scroll_id becomes stale, and a new one must be obtained with another query request with fetch_all = TRUE. All other parameters are ignored when the scroll_id parameter is supplied. For more information see examples using scroll_id here.
sort¶
Optional, the comma-separated fields to sort on. Prefix with “-” for descending order, otherwise in ascending order. Default: sort by matching scores in descending order.
facets¶
Optional, a single field or comma-separated fields to return facets, can only be used on non-free text fields. E.g. “facets=chembl.molecule_properties.full_mwt”. See examples of faceted queries here.
facet_size¶
Optional, an integer (1 <= facet_size <= 1000) that specifies how many buckets to return in a faceted query.
dotfield¶
Optional, can be used to control the format of the returned chemical object. If “dotfield” is true, the returned data object is returned flattened (no nested objects) using dotfield notation for key names. Default: false.
email¶
Optional, if you are regular users of our services, we encourage you to provide us an email, so that we can better track the usage or follow up with you.
Query syntax¶
Examples of query parameter “q”:
Fielded queries¶
q=chebi.xref.uniprot:P80175 # for matching value on a specific field
q=chebi.name:(acid alcohol) # multiple values for a field
q=chebi.name:(acid OR alcohol) # multiple values for a field using OR
q=_exists_:pubchem # having pubchem field
q=NOT _exists_:chebi # missing chebi field
Hint
For a list of available fields, see here.
Range queries¶
q=pubchem.exact_mass:<200
q=pubchem.exact_mass:>=500
q=pubchem.exact_mass:[200 TO 500] # bounded (including 200 and 500)
q=pubchem.exact_mass:{200 TO 500} # unbounded
Wildcard queries¶
Wildcard character “*” or “?” is supported in either simple queries or fielded queries:
q=chebi.name:acid*
Note
Wildcard character can not be the first character. It will be ignored.
Scrolling queries¶
If you want to return ALL results of a very large query, sometimes the paging method described above can take too long. In these cases, you can use a scrolling query. This is a two-step process that turns off database sorting to allow very fast retrieval of all query results. To begin a scrolling query, you first call the query endpoint as you normally would, but with an extra parameter fetch_all = TRUE. For example, a GET request to:
http://mychem.info/v1/query?q=_exists_:chebi&fields=chebi.name&fetch_all=TRUE
Returns the following object:
{
"_scroll_id": "FGluY2x1ZGVfY29udGV4dF91dWlkDnF1ZXJ5VGhlbkZldGNoAxY4REs4cmRsRFI1YWcxNXFpZ1VoN3JnAAAAAABJG1EWNWM0Skl3WWlRdWVzQkpIWGcyYTUwQRZqVUhTRnd5ZFFkV0hvSEN3WXdSU0h3AAAAAAAQb00WUngzX0FxcmNRRktxd0tnWUdUZEtMQRZ2bWg5LUc2SFQyQ19FTjA5Rl8xNEFBAAAAAABLL-4WTEthWGpxUFVUa0tqSXFJNTItMnlQUQ==",
"took": 422,
"total": 145633,
"max_score": 1,
"hits": [
{
"_id": "BTJXBZZBBNNTOV-UHFFFAOYSA-N",
"_score": 1,
"chebi": {
"_license": "http://bit.ly/2KAUCAm",
"name": "Linalyl benzoate"
}
},
{
"_id": "BUPRFDPUIJNOLS-UFYCRDLUSA-N",
"_score": 1,
"chebi": {
"_license": "http://bit.ly/2KAUCAm",
"name": "Tyr-Tyr-Met"
}
},
.
.
.
]
}
At this point, the first 1000 hits have been returned (of ~11,000 total), and a scroll has been set up for your query. To get the next batch of 1000 unordered results, simply execute a GET request to the following address, supplying the _scroll_id from the first step into the scroll_id parameter in the second step:
http://mychem.info/v1/query?scroll_id=cXVlcnlUaGVuRmV0Y2g7MTA7Njg4ODAwOTI6SmU0ck9oMTZUUHFyRXlYSTNPS2pMZzs2ODg4MDA5MTpKZTRyT2gxNlRQcXJFeVhJM09LakxnOzY4ODgwMDkzOkplNHJPaDE2VFBxckV5WEkzT0tqTGc7Njg4ODAwOTQ6SmU0ck9oMTZUUHFyRXlYSTNPS2pMZzs2ODg4MDEwMDpKZTRyT2gxNlRQcXJFeVhJM09LakxnOzY4ODgwMDk2OkplNHJPaDE2VFBxckV5WEkzT0tqTGc7Njg4ODAwOTg6SmU0ck9oMTZUUHFyRXlYSTNPS2pMZzs2ODg4MDA5NzpKZTRyT2gxNlRQcXJFeVhJM09LakxnOzY4ODgwMDk5OkplNHJPaDE2VFBxckV5WEkzT0tqTGc7Njg4ODAwOTU6SmU0ck9oMTZUUHFyRXlYSTNPS2pMZzswOw==
Hint
Your scroll will remain active for 1 minute from the last time you requested results from it. If your scroll expires before you get the last batch of results, you must re-request the scroll_id by setting fetch_all = TRUE as in step 1.
Hint
When you need to use this “scrolling query” feature via “fetch_all” parameter, we recommend you to use our Python client “biothings_client”.
Boolean operators and grouping¶
You can use AND/OR/NOT boolean operators and grouping to form complicated queries:
q=_exists_:chebi AND _exists_:pubchem AND operator
q=_exists_:chebi AND NOT _exists_:pubchem NOT operator
q=_exists_:chebi OR (_exists_:uniprot AND _exists_:pubchem) grouping with ()
Escaping reserved characters¶
If you need to use these reserved characters in your query, make sure to escape them using a back slash (”"):
+ - = && || > < ! ( ) { } [ ] ^ " ~ * ? : \ /
Returned object¶
A GET request like this:
http://mychem.info/v1/query?q=chebi.name:acid&fields=chebi.name
should return hits as:
{
"took": 22,
"total": 13462,
"max_score": 4.1048613,
"hits": [
{
"_id": "ZFSLODLOARCGLH-UHFFFAOYSA-N",
"_score": 4.1048613,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "cyanuric acid"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "isocyanuric acid"
}
]
},
{
"_id": "JRPHGDYSKGJTKZ-UHFFFAOYSA-N",
"_score": 4.066448,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "phosphoroselenoic acid"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "selenophosphoric acid"
}
]
},
{
"_id": "GQHALSXZONOXGJ-WHJCQOFKSA-N",
"_score": 4.0196724,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "clavaminic acid zwitterion"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "clavaminic acid"
}
]
},
{
"_id": "BONQGFBLZGPXMG-PIYBLCFFSA-N",
"_score": 4.0196724,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "dihydroclavaminic acid zwitterion"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "dihydroclavaminic acid"
}
]
},
{
"_id": "BPMFZUMJYQTVII-UHFFFAOYSA-N",
"_score": 4.0196724,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "guanidinoacetic acid zwitterion"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "guanidinoacetic acid"
}
]
},
{
"_id": "MPNWPLYZGCKKFY-VDTYLAMSSA-N",
"_score": 4.0196724,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "amidinoproclavaminic acid zwitterion"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "amidinoproclavaminic acid"
}
]
},
{
"_id": "NMCINKPVAOXDJH-VDTYLAMSSA-N",
"_score": 4.004429,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "proclavaminic acid zwitterion"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "proclavaminic acid"
}
]
},
{
"_id": "UYADDEKIZFRINK-LURJTMIESA-N",
"_score": 4.004429,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "deoxyamidinoproclavaminic acid zwitterion"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "deoxyamidinoproclavaminic acid"
}
]
},
{
"_id": "ZNOVTXRBGFNYRX-STQMWFEESA-N",
"_score": 4.004429,
"chebi": [
{
"_license": "http://bit.ly/2KAUCAm",
"name": "levomefolic acid"
},
{
"_license": "http://bit.ly/2KAUCAm",
"name": "5-methyltetrahydrofolic acid"
}
]
},
{
"_id": "WWVJUCNOSUHCFP-SDFLBUSUSA-N",
"_score": 4.004429,
"chebi": {
"_license": "http://bit.ly/2KAUCAm",
"name": "acid fuchsin (free acid form)"
}
}
]
}
“total” in the output gives the total number of matching hits, while the actual hits are returned under “hits” field. “size” parameter controls how many hits will be returned in one request (default is 10). Adjust “size” parameter and “from” parameter to retrieve the additional hits.
Faceted queries¶
If you need to perform a faceted query, you can pass an optional “facets” parameter.
A GET request like this:
http://mychem.info/v1/query?q=chebi.name:acid&fields=chebi.name&facets=chebi.xrefs.reactome&size=0
should return hits as:
{
"took": 112,
"total": 13462,
"max_score": null,
"facets": {
"chebi.xrefs.reactome": {
"_type": "terms",
"terms": [
{
"count": 19,
"term": "r-hsa-379048"
},
{
"count": 19,
"term": "r-hsa-749448"
},
{
"count": 19,
"term": "r-hsa-749452"
},
{
"count": 15,
"term": "r-hsa-383313"
},
{
"count": 13,
"term": "r-hsa-444191"
},
{
"count": 7,
"term": "r-hsa-194187"
},
{
"count": 7,
"term": "r-hsa-1989746"
},
{
"count": 7,
"term": "r-hsa-5627891"
},
{
"count": 7,
"term": "r-hsa-879585"
},
{
"count": 7,
"term": "r-hsa-9031856"
}
],
"other": 1562,
"missing": 7,
"total": 120
}
}
}
Batch queries via POST¶
Although making simple GET requests above to our chemical query service is sufficient for most use cases, there are times you might find it more efficient to make batch queries (e.g., retrieving chemical annotation for multiple chemicals). Fortunately, you can also make batch queries via POST requests when you need:
URL: http://mychem.info/v1/query
HTTP method: POST
Query parameters¶
q¶
Required, multiple query terms seperated by comma (also support “+” or white space), but no wildcard, e.g., ‘q=SDUQYLNIPVEERB-QPPQHZFASA-N,SESFRYSPDFLNCH-UHFFFAOYSA-N’
scopes¶
Optional, specify one or more fields (separated by comma) as the search “scopes”, e.g., “scopes=chebi”. The available “fields” can be passed to “scopes” parameter are listed here. Default:
fields¶
Optional, a comma-separated string to limit the fields returned from the matching chem hits. The supported field names can be found from any chemical object. Note that it supports dot notation, and wildcards as well, e.g., you can pass “chebi”, “chebi.name”, or “dbnsfp.products.*”. If “fields=all”, all available fields will be returned. Default: “all”.
email¶
Optional, if you are regular users of our services, we encourage you to provide us an email, so that we can better track the usage or follow up with you.
Example code¶
Unlike GET requests, you can easily test them from browser, make a POST request is often done via a piece of code. Here is a sample python snippet using httplib2 module:
import httplib2
h = httplib2.Http()
headers = {'content-type': 'application/x-www-form-urlencoded'}
params = 'q=CHEBI:175901,CHEBI:41237&scopes=chebi.id&fields=chebi.name'
res, con = h.request('http://mychem.info/v1/query', 'POST', params, headers=headers)
or this example using requests module:
import requests
params = {'q': 'CHEBI:175901,CHEBI:41237', 'scopes': 'chebi.id', 'fields': 'chebi.name'}
res = requests.post('http://mychem.info/v1/query', params)
con = res.json()
Returned object¶
Returned result (the value of “con” variable above) from above example code should look like this:
[
{
"query": "CHEBI:175901",
"_id": "SDUQYLNIPVEERB-QPPQHZFASA-N",
"_score": 10.408574,
"chebi": {
"_license": "http://bit.ly/2KAUCAm",
"name": "gemcitabine"
}
},
{
"query": "CHEBI:41237",
"_id": "SESFRYSPDFLNCH-UHFFFAOYSA-N",
"_score": 10.413283,
"chebi": {
"_license": "http://bit.ly/2KAUCAm",
"name": "benzyl benzoate"
}
}
]
Tip
“query” field in returned object indicates the matching query term.
If a query term has no match, it will return with “notfound” field as “true”:
[
...,
{'query': '...',
'notfound': true},
...
]
Chemical annotation service¶
This page describes the reference for the MyChem.info chemical annotation web service. It’s also recommended to try it live on our interactive API page.
Service endpoint¶
http://mychem.info/v1/chem
GET request¶
Obtaining the chemical annotation via our web service is as simple as calling this URL:
http://mychem.info/v1/chem/<chemid>
chemid above is any one of several common chemical identifiers: InChIKey, ChEMBLID, ChEBI identifier, PubChem CID, UNII.
By default, this will return the complete chemical annotation object in JSON format. See here for an example and here for more details. If the input chemid is not valid, 404 (NOT FOUND) will be returned.
Optionally, you can pass a “fields” parameter to return only the annotation you want (by filtering returned object fields):
http://mychem.info/v1/chem/KTUFNOKKBVMGRW-UHFFFAOYSA-N?fields=chembl
“fields” accepts any attributes (a.k.a fields) available from the chemical object. Multiple attributes should be separated by commas. If an attribute is not available for a specific chemical object, it will be ignored. Note that the attribute names are case-sensitive.
Just like the chemical query service, you can also pass a “callback” parameter to make a JSONP call.
Query parameters¶
fields¶
Optional, can be a comma-separated fields to limit the fields returned from the chemical object. If “fields=all”, all available fields will be returned. Note that it supports dot notation as well, e.g., you can pass “chebi.name”. Default: “fields=all”.
filter¶
Alias for “fields” parameter.
email¶
Optional, if you are regular users of our services, we encourage you to provide us an email, so that we can better track the usage or follow up with you.
Returned object¶
A GET request like this:
http://mychem.info/v1/chem/KTUFNOKKBVMGRW-UHFFFAOYSA-N?fields=pubchem
should return a chemical object below:
{
"_id": "KTUFNOKKBVMGRW-UHFFFAOYSA-N",
"_version": 1,
"pubchem": {
"_license": "http://bit.ly/2AqoLOc",
"chiral_atom_count": 0,
"chiral_bond_count": 0,
"cid": 5291,
"complexity": 706,
"covalently-bonded_unit_count": 1,
"defined_atom_stereocenter_count": 0,
"defined_bond_stereocenter_count": 0,
"exact_mass": 493.259,
"formal_charge": 0,
"heavy_atom_count": 37,
"hydrogen_bond_acceptor_count": 7,
"hydrogen_bond_donor_count": 2,
"inchi": "InChI=1S/C29H31N7O/c1-21-5-10-25(18-27(21)34-29-31-13-11-26(33-29)24-4-3-12-30-19-24)32-28(37)23-8-6-22(7-9-23)20-36-16-14-35(2)15-17-36/h3-13,18-19H,14-17,20H2,1-2H3,(H,32,37)(H,31,33,34)",
"inchi_key": "KTUFNOKKBVMGRW-UHFFFAOYSA-N",
"isotope_atom_count": 0,
"iupac": {
"traditional": "4-[(4-methylpiperazino)methyl]-N-[4-methyl-3-[[4-(3-pyridyl)pyrimidin-2-yl]amino]phenyl]benzamide"
},
"molecular_formula": "C29H31N7O",
"molecular_weight": 493.615,
"monoisotopic_weight": 493.259,
"rotatable_bond_count": 7,
"smiles": {
"isomeric": "CC1=C(C=C(C=C1)NC(=O)C2=CC=C(C=C2)CN3CCN(CC3)C)NC4=NC=CC(=N4)C5=CN=CC=C5"
},
"tautomers_count": 72,
"topological_polar_surface_area": 86.3,
"undefined_atom_stereocenter_count": 0,
"undefined_bond_stereocenter_count": 0,
"xlogp": 3.5
}
}
Batch queries via POST¶
Although making simple GET requests above to our chemical query service is sufficient in most use cases, there are some times you might find it’s easier to batch query (e.g., retrieving chemical annotations for multiple chemicals). Fortunately, you can also make batch queries via POST requests when you need:
URL: http://mychem.info/v1/chem
HTTP method: POST
Query parameters¶
ids¶
Required. Accept multiple chemical ids separated by comma, e.g., “ids=SDUQYLNIPVEERB-QPPQHZFASA-N,SESFRYSPDFLNCH-UHFFFAOYSA-N,SHGAZHPCJJPHSC-ZVCIMWCZSA-N”. Note that currently we only take the input ids up to 1000 maximum, the rest will be omitted.
fields¶
Optional, can be a comma-separated fields to limit the fields returned from the matching hits. If “fields=all”, all available fields will be returned. Note that it supports dot notation as well, e.g., you can pass “chembl” or “chebi.name”. Default: “all”.
email¶
Optional, if you are regular users of our services, we encourage you to provide us an email, so that we can better track the usage or follow up with you.
Example code¶
Unlike GET requests, you can easily test them from browser, make a POST request is often done via a piece of code, still trivial of course. Here is a sample python snippe using httplib2 modulet:
import httplib2
h = httplib2.Http()
headers = {'content-type': 'application/x-www-form-urlencoded'}
params = 'ids=SDUQYLNIPVEERB-QPPQHZFASA-N,SESFRYSPDFLNCH-UHFFFAOYSA-N&fields=chebi.name'
res, con = h.request('http://mychem.info/v1/chem', 'POST', params, headers=headers)
or this example using requests module:
import requests
params = {'ids': 'SDUQYLNIPVEERB-QPPQHZFASA-N,SESFRYSPDFLNCH-UHFFFAOYSA-N', 'fields': 'chebi.name'}
res = request.post('http://mychem.info/v1/chem', params)
con = res.json()
Returned object¶
Returned result (the value of “con” variable above) from above example code should look like this:
[
{
"query": "SDUQYLNIPVEERB-QPPQHZFASA-N",
"_id": "SDUQYLNIPVEERB-QPPQHZFASA-N",
"_version": 1,
"chebi": {
"_license": "http://bit.ly/2KAUCAm",
"name": "gemcitabine"
}
},
{
"query": "SESFRYSPDFLNCH-UHFFFAOYSA-N",
"_id": "SESFRYSPDFLNCH-UHFFFAOYSA-N",
"_version": 1,
"chebi": {
"_license": "http://bit.ly/2KAUCAm",
"name": "benzyl benzoate"
}
}
]
Server response¶
The MyChem.info server returns a variety of query responses, and response status codes. They are listed here.
Note
These examples show query responses using the python requests package.
Status code 200¶
A 200 status code indicates a successful query, and is accompanied by the query response payload.
In [1]: import requests
In [2]: r = requests.get('http://mychem.info/v1/query?q=_exists_:chebi')
In [3]: r.status_code
Out[3]: 200
In [4]: data = r.json()
In [5]: data.keys()
Out[5]: dict_keys(['total', 'max_score', 'took', 'hits'])
Status code 400¶
A 400 status code indicates an improperly formed query, and is accompanied by a response payload describing the source of the error.
In [6]: r = requests.get('http://mychem.info/v1/query?q=_exists_:chebi&size=u')
In [7]: r.status_code
Out[7]: 400
In [8]: data = r.json()
In [9]: data
Out[9]:
{'error': "Expected 'size' parameter to have integer type. Couldn't convert 'u' to integer",
'success': False}
Status code 404¶
A 404 status code indicates either an unrecognized URL, as in (/query is misspelled /quer resulting in an unrecognized URL):
In [10]: r = requests.get('http://mychem.info/v1/quer?q=_exists_:chebi')
In [11]: r.status_code
Out[11]: 404
or, for the /chem endpoint, a 404 status code could be from querying for a nonexistent chemical ID, as in:
In [12]: r = requests.get('http://mychem.info/v1/chem/5')
In [13]: r.status_code
Out[13]: 404
In [14]: data = r.json()
In [15]: data
Out[15]:
{'error': "ID '5' not found",
'success': False}
Status code 5xx¶
Any 5xx status codes are the result of uncaught query errors. Ideally, these should never occur. We routinely check our logs for these types of errors and add code to catch them, but if you see any status 5xx responses, please submit a bug report to help@mychem.info.
Biothings_client python module¶
You can access the MyChem.info services programmatically with our biothings_client unified python client.